This is going to be my first review I've ever made on a manga, but I'm going to take this as some form of experiment and see if it's helpful enough to convince people to read this underrated (or slightly obscure) piece of art. Also this will most likely contain spoilers.
Note: I made this review while being only through 16 chapters (vol 3).
While it is merely an ongoing, Isekai Yakuzahime has a lot of potential and might be the most fascinating work from Hiroki Miyashita so far that I've seen at least (this time around he isn't doing the Story, which differs from his previous works). At first, I didn't know much about this artist and I read a bit of Kettou Saiban which had really amazing art style just like this one, along with surprisingly well choreographed fighting scenes, but it felt plain storywise and I don't think it was satisfying enough. Now surprisingly, Kettou Saiban and Isekai Yakuzahime are pretty damn similar, not because of the art style but because of the inherent world and context they are following. They both have a MC that's visibly endangered by society or the system, which they want to fight against or rebel against it. This is something I will explain a bit further later on...
So, the first issue with this work that's probably making people be a bit reluctant in reading it is most likely pretty obvious. It's an Isekai. And not only that but it's also a Gender Bender. Basically this is like Youjo Senki pretty much where you have an old man reincarnating in the body of a young girl but also getting isekai'd in the process (its basically the isekai/reincarnation combo you see everywhere else). Now, we all know what Isekai is... we consume it probably on a daily basis because its the trendiest thematic in manga and anime as well (also light novels too), but when you are doing an Isekai related work, the difficulty is to make it stand out from the rest. This is hard because everything tends to have recycled ideas, the moment a popular work like Slime datta ken for example or idk Shield Hero pops in there's eventually some sort of influence going on and you start witnessing more and more works that are similar to what you saw previously. The other issue is regarding OP MCs and Isekai Yakuzahime is no exception... the MC is also very strong in here, she has some kind of divine or godlike power, not sure what exactly it is (will probably be more developed on that information at some point in this manga). But basically even though the fights look like its not winnable, you know the MC is just gonna stomp them over and win the fight anyway... so this might be an aspect that will most likely end up being too predictable or boring as you read through (but because this is an ongoing and will probably change in the future, take this with a grain of salt). Still, the way the fights are realized and with how great the paneling and stuff is, along with some really tense encounters with the enemy, without a doubt this compensates in one way or another the boredom, you could say its like an icy frost on top of a cake that doesn't taste super good inside basically.
Something really fascinating about this manga is regarding the context of the story and how there's a lot of potential adventure wise. The MC enters a world that's typical of any Fantasy setting out there, but the difference is that the world seems to not be a dreamland, there are a lot of problems on many aspects and it seems like it's pure chaos whenever the MC travels in one place or another. As you probably already know if you read chapter 1 or 2, the MC is running away from an organization that's after their lives for X reason (most likely political) and they always have to be on the move. Of course, this is great because it means they will forcefully undergo an adventure, but this leaves a lot of questions unanswered, because you don't really know why they are after their lives for, what is the goal of the enemy? The mystery element in it is great because everything seems to be very dark, it has a lot of shady organizations, demons meddling in human affairs and this enforces the idea that everything around the MC is pretty much corrupted or prone to corruption in one way or another. Of course, be careful if you are a sensitive person, some of the stories of the characters they meet throughout their travel are tragic, deep and depressing sometimes. There are mentions of rape, human trafficking and a lot of f*cked up stuff along the way. So if you recommend this to someone, make sure to inform them beforehand about those elements.
Now, the MC is someone who has morals, despite being a Yakuza they aren't bad by their core, they are bad in the way they are very prone to violence, usually talks super rude to others and definitely doesn't like people who have a lot of powers but dont know how to handle it properly. They save a lot of people throughout their journey, dealing with the corruption of those places they happen to stay only temporarily. But the MC also says at one point: "I'm not that glorious. Ever since the past, I've had issues with bigshots. I just felt a burning desire to hit that beardie." which does align with the character's previous life and overall personality as a Yakuza.
Another thing I like in here is the way the monsters (demons) are designed. It's so unique, it feels like they came straight out of Cthulhu mythos. They have some really grotesque appearances, a lot of tentacles, eyeballs and stuff that remotely looks like distorted human flesh. It’s horrifying, like I highkey feel some sort of dread just from looking at this one panel...
But there's a lot of good elements here and there, like having a strong female lead who doesn’t give a damn and just being overall badass is satisfying, it’s cool (despite the fact its a gender bender, it’s still pretty nice). One part I forgot to mention is that there are some references packed in this manga, a lot of typical Yakuza slang and Japanese idioms, the peculiar tattoo of a divine figure on the MC’s back (not sure what it represents) but apparently it’s some kind of guardian goddess and I’m pretty sure it has to be related to some religious figure (like Buddhism) or folklore. Maybe I will find out later on, I just know that the original self of the MC (the oldman) had that tattoo, so it most likely transferred/passed on to the girl during the reincarnation/isekai process. But this is also a direct hint to Yakuza tattoos, as you know, a lot of Yakuza have tattoos on their back or their arms (anywhere really because there are multiple styles, like hikae or nukibori but its usually those places) and they always focus on Japanese mythology or history, they all have some kind of meaning to them. In any case, there are some details here and there that may be interesting to pay attention to, not sure how important they are to the story but I know that the MC’s peculiar moral messages do have an impact on the characters and helps them in their growth as a person.
Also, because it's an Isekai, some stuff about the world have to be explained, the countries, the people, the business that are happening in those towns, the "Guiding Tree" (I guess it works like Hamon in this world but it serves as someone's DNA or some sort), stuff related to magic in general... There's just a fat ton of information (not like it's a bad thing) but this means it's kind of rich content wise aside from the cool fights and I hope they keep adding more stuff to learn about in this manga, otherwise it will significantly affect the work for sure.
In any case, I hope this was convincing enough to make anyone who reads this review to read this ongoing manga, some people aren’t fond of reading ongoings but you can put it in PTR at least if you have some kind of interest for this. If you like good art style, this is a must, you will definitely not be disappointed. As I hopefully pray that Isekai Yakuzahime will gain more traction and have way more volumes than its predecessor, it would be really unfortunate if it gets axed at vol 4 as well or something like that. So I hope this keeps up and that the creators won’t disappoint.